use Glide for a lower priority pass of higher quality thumbnails

android/app/src/main/java/deckers/thibault/aves/channelhandlers/ImageDecodeTask.java

@@ -12,6 +12,7 @@ import android.provider.MediaStore;
 import android.util.Log;
 import android.util.Size;
 
+import androidx.annotation.Nullable;
 import androidx.annotation.RequiresApi;
 
 import com.bumptech.glide.Glide;
@@ -35,14 +36,15 @@ public class ImageDecodeTask extends AsyncTask<ImageDecodeTask.Params, Void, Ima
 
     static class Params {
         ImageEntry entry;
-        int width, height;
+        Integer width, height, defaultSize;
         MethodChannel.Result result;
 
-        Params(ImageEntry entry, int width, int height, MethodChannel.Result result) {
+        Params(ImageEntry entry, @Nullable Integer width, @Nullable Integer height, Integer defaultSize, MethodChannel.Result result) {
             this.entry = entry;
             this.width = width;
             this.height = height;
             this.result = result;
+            this.defaultSize = defaultSize;
         }
     }
 
@@ -69,6 +71,12 @@ public class ImageDecodeTask extends AsyncTask<ImageDecodeTask.Params, Void, Ima
         Bitmap bitmap = null;
         if (!this.isCancelled()) {
             Exception exception = null;
+            Integer w = p.width;
+            Integer h = p.height;
+            // fetch low quality thumbnails when size is not specified
+            if (w == null || h == null || w == 0 || h == 0) {
+                p.width = p.defaultSize;
+                p.height = p.defaultSize;
                 try {
                     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
                         bitmap = getThumbnailBytesByResolver(p);
@@ -78,8 +86,9 @@ public class ImageDecodeTask extends AsyncTask<ImageDecodeTask.Params, Void, Ima
                 } catch (Exception e) {
                     exception = e;
                 }
+            }
 
-            // fallback if the native methods failed
+            // fallback if the native methods failed or for higher quality thumbnails
             try {
                 if (bitmap == null) {
                     bitmap = getThumbnailByGlide(p);
@@ -108,8 +117,9 @@ public class ImageDecodeTask extends AsyncTask<ImageDecodeTask.Params, Void, Ima
     @RequiresApi(api = Build.VERSION_CODES.Q)
     private Bitmap getThumbnailBytesByResolver(Params params) throws IOException {
         ImageEntry entry = params.entry;
-        int width = params.width;
+        Integer width = params.width;
-        int height = params.height;
+        Integer height = params.height;
+//        Log.d(LOG_TAG, "getThumbnailBytesByResolver width=" + width + ", path=" + entry.path);
 
         ContentResolver resolver = activity.getContentResolver();
         return resolver.loadThumbnail(entry.uri, new Size(width, height), null);
@@ -141,6 +151,7 @@ public class ImageDecodeTask extends AsyncTask<ImageDecodeTask.Params, Void, Ima
         ImageEntry entry = params.entry;
         int width = params.width;
         int height = params.height;
+//        Log.d(LOG_TAG, "getThumbnailByGlide width=" + width + ", path=" + entry.path);
 
         // add signature to ignore cache for images which got modified but kept the same URI
         Key signature = new ObjectKey("" + entry.dateModifiedSecs + entry.width + entry.orientationDegrees);

android/app/src/main/java/deckers/thibault/aves/channelhandlers/ImageFileHandler.java

@@ -7,6 +7,8 @@ import android.os.Looper;
 
 import androidx.annotation.NonNull;
 
+import com.bumptech.glide.Glide;
+
 import java.util.Map;
 
 import deckers.thibault.aves.model.ImageEntry;
@@ -39,6 +41,10 @@ public class ImageFileHandler implements MethodChannel.MethodCallHandler {
             case "getThumbnail":
                 new Thread(() -> getThumbnail(call, new MethodResultWrapper(result))).start();
                 break;
+            case "clearSizedThumbnailDiskCache":
+                new Thread(() -> Glide.get(activity).clearDiskCache()).start();
+                result.success(null);
+                break;
             case "rename":
                 new Thread(() -> rename(call, new MethodResultWrapper(result))).start();
                 break;
@@ -55,12 +61,13 @@ public class ImageFileHandler implements MethodChannel.MethodCallHandler {
         Map entryMap = call.argument("entry");
         Integer width = call.argument("width");
         Integer height = call.argument("height");
-        if (entryMap == null || width == null || height == null) {
+        Integer defaultSize = call.argument("defaultSize");
+        if (entryMap == null || defaultSize == null) {
             result.error("getThumbnail-args", "failed because of missing arguments", null);
             return;
         }
         ImageEntry entry = new ImageEntry(entryMap);
-        new ImageDecodeTask(activity).execute(new ImageDecodeTask.Params(entry, width, height, result));
+        new ImageDecodeTask(activity).execute(new ImageDecodeTask.Params(entry, width, height, defaultSize, result));
     }
 
     private void getImageEntry(@NonNull MethodCall call, @NonNull MethodChannel.Result result) {

lib/model/image_entry.dart

@@ -266,7 +266,7 @@ class ImageEntry {
     try {
       final addresses = await servicePolicy.call(
         () => Geocoder.local.findAddressesFromCoordinates(coordinates),
-        priority: ServiceCallPriority.background,
+        priority: ServiceCallPriority.getLocation,
       );
       if (addresses != null && addresses.isNotEmpty) {
         final address = addresses.first;

lib/services/image_file_service.dart

@@ -14,8 +14,6 @@ class ImageFileService {
   static final StreamsChannel byteChannel = StreamsChannel('deckers.thibault/aves/imagebytestream');
   static final StreamsChannel opChannel = StreamsChannel('deckers.thibault/aves/imageopstream');
 
-  static const thumbnailPriority = ServiceCallPriority.asap;
-
   static Future<void> getImageEntries() async {
     try {
       await platform.invokeMethod('getImageEntries');
@@ -64,28 +62,36 @@ class ImageFileService {
   static Future<Uint8List> getThumbnail(ImageEntry entry, int width, int height, {Object taskKey}) {
     return servicePolicy.call(
       () async {
-        if (width > 0 && height > 0) {
         try {
           final result = await platform.invokeMethod('getThumbnail', <String, dynamic>{
             'entry': entry.toMap(),
             'width': width,
             'height': height,
+            'defaultSize': 256,
           });
           return result as Uint8List;
         } on PlatformException catch (e) {
           debugPrint('getThumbnail failed with code=${e.code}, exception=${e.message}, details=${e.details}');
         }
-        }
         return Uint8List(0);
       },
-      priority: thumbnailPriority,
+//      debugLabel: 'getThumbnail width=$width, height=$height entry=${entry.filenameWithoutExtension}',
+      priority: width == 0 || height == 0 ? ServiceCallPriority.getFastThumbnail : ServiceCallPriority.getSizedThumbnail,
       key: taskKey,
     );
   }
 
-  static bool cancelThumbnail(Object taskKey) => servicePolicy.pause(taskKey, thumbnailPriority);
+  static Future<void> clearSizedThumbnailDiskCache() async {
+    try {
+      return platform.invokeMethod('clearSizedThumbnailDiskCache');
+    } on PlatformException catch (e) {
+      debugPrint('clearSizedThumbnailDiskCache failed with code=${e.code}, exception=${e.message}, details=${e.details}');
+    }
+  }
 
-  static Future<T> resumeThumbnail<T>(Object taskKey) => servicePolicy.resume<T>(taskKey, thumbnailPriority);
+  static bool cancelThumbnail(Object taskKey) => servicePolicy.pause(taskKey, [ServiceCallPriority.getFastThumbnail, ServiceCallPriority.getSizedThumbnail]);
+
+  static Future<T> resumeThumbnail<T>(Object taskKey) => servicePolicy.resume<T>(taskKey);
 
   static Stream<ImageOpEvent> delete(Iterable<ImageEntry> entries) {
     try {

lib/services/metadata_service.dart

@@ -50,7 +50,7 @@ class MetadataService {
         }
         return null;
       },
-      priority: ServiceCallPriority.background,
+      priority: ServiceCallPriority.getMetadata,
     );
   }
 

lib/services/service_policy.dart

@@ -2,36 +2,37 @@ import 'dart:async';
 import 'dart:collection';
 
 import 'package:flutter/foundation.dart';
+import 'package:tuple/tuple.dart';
 
 final ServicePolicy servicePolicy = ServicePolicy._private();
 
 class ServicePolicy {
-  final Map<Object, _Task> _paused = {};
+  final Map<Object, Tuple2<int, _Task>> _paused = {};
-  final Queue<_Task> _asapQueue = Queue(), _normalQueue = Queue(), _backgroundQueue = Queue();
+  final SplayTreeMap<int, Queue<_Task>> _queues = SplayTreeMap();
-  List<Queue<_Task>> _queues;
   _Task _running;
 
-  ServicePolicy._private() {
+  ServicePolicy._private();
-    _queues = [_asapQueue, _normalQueue, _backgroundQueue];
-  }
 
   Future<T> call<T>(
     Future<T> Function() platformCall, {
-    ServiceCallPriority priority = ServiceCallPriority.normal,
+    int priority = ServiceCallPriority.normal,
     String debugLabel,
     Object key,
   }) {
-    var task = _paused.remove(key);
+    _Task task;
-    if (task != null) {
+    final priorityTask = _paused.remove(key);
+    if (priorityTask != null) {
       debugPrint('resume task with key=$key');
+      priority = priorityTask.item1;
+      task = priorityTask.item2;
     }
     var completer = task?.completer ?? Completer<T>();
     task ??= _Task(
       () async {
-//      if (debugLabel != null) debugPrint('$runtimeType $debugLabel start');
+        if (debugLabel != null) debugPrint('$runtimeType $debugLabel start');
         final result = await platformCall();
         completer.complete(result);
-//      if (debugLabel != null) debugPrint('$runtimeType $debugLabel completed');
+        if (debugLabel != null) debugPrint('$runtimeType $debugLabel completed');
         _running = null;
         _pickNext();
       },
@@ -43,62 +44,46 @@ class ServicePolicy {
     return completer.future;
   }
 
-  Future<T> resume<T>(Object key, ServiceCallPriority priority) {
+  Future<T> resume<T>(Object key) {
-    var task = _paused.remove(key);
+    final priorityTask = _paused.remove(key);
-    if (task == null) return null;
+    if (priorityTask == null) return null;
+    final priority = priorityTask.item1;
+    final task = priorityTask.item2;
     _getQueue(priority).addLast(task);
     _pickNext();
     return task.completer.future;
   }
 
-  Queue<_Task> _getQueue(ServiceCallPriority priority) {
+  Queue<_Task> _getQueue(int priority) => _queues.putIfAbsent(priority, () => Queue<_Task>());
-    Queue<_Task> queue;
-    switch (priority) {
-      case ServiceCallPriority.asap:
-        queue = _asapQueue;
-        break;
-      case ServiceCallPriority.background:
-        queue = _backgroundQueue;
-        break;
-      case ServiceCallPriority.normal:
-      default:
-        queue = _normalQueue;
-        break;
-    }
-    return queue;
-  }
 
   void _pickNext() {
     if (_running != null) return;
-    final queue = _queues.firstWhere((q) => q.isNotEmpty, orElse: () => null);
+    final queue = _queues.entries.firstWhere((kv) => kv.value.isNotEmpty, orElse: () => null)?.value;
     _running = queue?.removeFirst();
     _running?.callback?.call();
   }
 
-  bool cancel(Object key, ServiceCallPriority priority) {
+  bool _takeOut(Object key, Iterable<int> priorities, void Function(int priority, _Task task) action) {
-    var cancelled = false;
+    var out = false;
+    priorities.forEach((priority) {
       final queue = _getQueue(priority);
       final tasks = queue.where((task) => task.key == key).toList();
       tasks.forEach((task) {
         if (queue.remove(task)) {
-        cancelled = true;
+          out = true;
-        task.completer.completeError(CancelledException());
+          action(priority, task);
         }
       });
-    return cancelled;
+    });
+    return out;
   }
 
-  bool pause(Object key, ServiceCallPriority priority) {
+  bool cancel(Object key, Iterable<int> priorities) {
-    var paused = false;
+    return _takeOut(key, priorities, (priority, task) => task.completer.completeError(CancelledException()));
-    final queue = _getQueue(priority);
-    final tasks = queue.where((task) => task.key == key).toList();
-    tasks.forEach((task) {
-      if (queue.remove(task)) {
-        paused = true;
-        _paused.putIfAbsent(key, () => task);
   }
-    });
+
-    return paused;
+  bool pause(Object key, Iterable<int> priorities) {
+    return _takeOut(key, priorities, (priority, task) => _paused.putIfAbsent(key, () => Tuple2(priority, task)));
   }
 
   bool isPaused(Object key) => _paused.containsKey(key);
@@ -114,4 +99,10 @@ class _Task {
 
 class CancelledException {}
 
-enum ServiceCallPriority { asap, normal, background }
+class ServiceCallPriority {
+  static const int getFastThumbnail = 100;
+  static const int getSizedThumbnail = 200;
+  static const int normal = 500;
+  static const int getMetadata = 1000;
+  static const int getLocation = 1000;
+}

lib/utils/constants.dart

@@ -22,9 +22,6 @@ class Constants {
   // ref _PopupMenuRoute._kMenuDuration
   static const popupMenuTransitionDuration = Duration(milliseconds: 300);
 
-  // TODO TLAD smarter sizing, but shouldn't only depend on `extent` so that it doesn't reload during gridview scaling
-  static const double thumbnailCacheExtent = 50;
-
   static const svgBackground = Colors.white;
   static const svgColorFilter = ColorFilter.mode(svgBackground, BlendMode.dstOver);
 

lib/widgets/album/thumbnail/raster.dart

@@ -1,5 +1,6 @@
+import 'dart:math';
+
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/utils/constants.dart';
 import 'package:aves/widgets/common/image_providers/thumbnail_provider.dart';
 import 'package:aves/widgets/common/image_providers/uri_image_provider.dart';
 import 'package:aves/widgets/common/transition_image.dart';
@@ -24,7 +25,7 @@ class ThumbnailRasterImage extends StatefulWidget {
 }
 
 class _ThumbnailRasterImageState extends State<ThumbnailRasterImage> {
-  ThumbnailProvider _imageProvider;
+  ThumbnailProvider _fastThumbnailProvider, _sizedThumbnailProvider;
 
   ImageEntry get entry => widget.entry;
 
@@ -32,6 +33,11 @@ class _ThumbnailRasterImageState extends State<ThumbnailRasterImage> {
 
   Object get heroTag => widget.heroTag;
 
+  // we standardize the thumbnail loading dimension by taking the nearest larger power of 2
+  // so that there are less variants of the thumbnails to load and cache
+  // it increases the chance of cache hit when loading similarly sized columns (e.g. on orientation change)
+  double get requestExtent => pow(2, (log(extent) / log(2)).ceil()).toDouble();
+
   @override
   void initState() {
     super.initState();
@@ -53,7 +59,12 @@ class _ThumbnailRasterImageState extends State<ThumbnailRasterImage> {
     super.dispose();
   }
 
-  void _initProvider() => _imageProvider = ThumbnailProvider(entry: entry, extent: Constants.thumbnailCacheExtent);
+  void _initProvider() {
+    _fastThumbnailProvider = ThumbnailProvider(entry: entry);
+    if (!entry.isVideo) {
+      _sizedThumbnailProvider = ThumbnailProvider(entry: entry, extent: requestExtent);
+    }
+  }
 
   void _pauseProvider() {
     final isScrolling = widget.isScrollingNotifier?.value ?? false;
@@ -61,14 +72,26 @@ class _ThumbnailRasterImageState extends State<ThumbnailRasterImage> {
     // the retrieval task queue can pile up for thumbnails that got disposed
     // in this case we pause the image retrieval task to get it out of the queue
     if (isScrolling) {
-      _imageProvider?.pause();
+      _fastThumbnailProvider?.pause();
+      _sizedThumbnailProvider?.pause();
     }
   }
 
   @override
   Widget build(BuildContext context) {
-    final image = Image(
+    final fastImage = Image(
-      image: _imageProvider,
+      image: _fastThumbnailProvider,
+      width: extent,
+      height: extent,
+      fit: BoxFit.cover,
+    );
+    final image = _sizedThumbnailProvider == null
+        ? fastImage
+        : Image(
+            frameBuilder: (context, child, frame, wasSynchronouslyLoaded) {
+              return frame == null ? fastImage : child;
+            },
+            image: _sizedThumbnailProvider,
             width: extent,
             height: extent,
             fit: BoxFit.cover,
@@ -78,7 +101,7 @@ class _ThumbnailRasterImageState extends State<ThumbnailRasterImage> {
         : Hero(
             tag: heroTag,
             flightShuttleBuilder: (flight, animation, direction, fromHero, toHero) {
-              ImageProvider heroImageProvider = _imageProvider;
+              ImageProvider heroImageProvider = _fastThumbnailProvider;
               if (!entry.isVideo && !entry.isSvg) {
                 final imageProvider = UriImage(
                   uri: entry.uri,

lib/widgets/album/thumbnail_collection.dart

@@ -14,6 +14,7 @@ import 'package:aves/widgets/common/icons.dart';
 import 'package:aves/widgets/common/scroll_thumb.dart';
 import 'package:draggable_scrollbar/draggable_scrollbar.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter/rendering.dart';
 import 'package:provider/provider.dart';
 import 'package:tuple/tuple.dart';
 
@@ -32,6 +33,7 @@ class ThumbnailCollection extends StatelessWidget {
           final mqSize = mq.item1;
           final mqHorizontalPadding = mq.item2;
           TileExtentManager.applyTileExtent(mqSize, mqHorizontalPadding, _tileExtentNotifier);
+          final cacheExtent = TileExtentManager.extentMaxForSize(mqSize);
 
           // do not replace by Provider.of<CollectionLens>
           // so that view updates on collection filter changes
@@ -47,6 +49,7 @@ class ThumbnailCollection extends StatelessWidget {
                 appBarHeightNotifier: _appBarHeightNotifier,
                 isScrollingNotifier: _isScrollingNotifier,
                 scrollController: PrimaryScrollController.of(context),
+                cacheExtent: cacheExtent,
               );
 
               final scaler = GridScaleGestureDetector(
@@ -91,6 +94,7 @@ class CollectionScrollView extends StatefulWidget {
   final ValueNotifier<double> appBarHeightNotifier;
   final ValueNotifier<bool> isScrollingNotifier;
   final ScrollController scrollController;
+  final double cacheExtent;
 
   const CollectionScrollView({
     @required this.scrollableKey,
@@ -99,6 +103,7 @@ class CollectionScrollView extends StatefulWidget {
     @required this.appBarHeightNotifier,
     @required this.isScrollingNotifier,
     @required this.scrollController,
+    @required this.cacheExtent,
   });
 
   @override
@@ -149,6 +154,7 @@ class _CollectionScrollViewState extends State<CollectionScrollView> {
       // workaround to prevent scrolling the app bar away
       // when there is no content and we use `SliverFillRemaining`
       physics: collection.isEmpty ? const NeverScrollableScrollPhysics() : null,
+      cacheExtent: widget.cacheExtent,
       slivers: [
         appBar,
         collection.isEmpty

lib/widgets/common/image_providers/thumbnail_provider.dart

@@ -9,8 +9,8 @@ import 'package:flutter/material.dart';
 class ThumbnailProvider extends ImageProvider<ThumbnailProviderKey> {
   ThumbnailProvider({
     @required this.entry,
-    @required this.extent,
+    this.extent = 0,
-    this.scale = 1.0,
+    this.scale = 1,
   })  : assert(entry != null),
         assert(extent != null),
         assert(scale != null) {

lib/widgets/debug_page.dart

@@ -8,6 +8,7 @@ import 'package:aves/model/metadata_db.dart';
 import 'package:aves/model/settings.dart';
 import 'package:aves/services/android_app_service.dart';
 import 'package:aves/services/android_file_service.dart';
+import 'package:aves/services/image_file_service.dart';
 import 'package:aves/utils/android_file_utils.dart';
 import 'package:aves/utils/file_utils.dart';
 import 'package:aves/widgets/common/data_providers/media_query_data_provider.dart';
@@ -65,7 +66,7 @@ class DebugPageState extends State<DebugPage> {
                 Tab(icon: Icon(OMIcons.whatshot)),
                 Tab(icon: Icon(OMIcons.settings)),
                 Tab(icon: Icon(OMIcons.sdStorage)),
-                Tab(text: 'Env'),
+                Tab(icon: Icon(OMIcons.android)),
               ],
             ),
           ),
@@ -108,8 +109,10 @@ class DebugPageState extends State<DebugPage> {
         const Divider(),
         Row(
           children: [
-            Text('Image cache: ${imageCache.currentSize} items, ${formatFilesize(imageCache.currentSizeBytes)}'),
+            Expanded(
-            const Spacer(),
+              child: Text('Image cache:\n\t${imageCache.currentSize}/${imageCache.maximumSize} items\n\t${formatFilesize(imageCache.currentSizeBytes)}/${formatFilesize(imageCache.maximumSizeBytes)}'),
+            ),
+            const SizedBox(width: 8),
             RaisedButton(
               onPressed: () {
                 imageCache.clear();
@@ -121,8 +124,10 @@ class DebugPageState extends State<DebugPage> {
         ),
         Row(
           children: [
-            Text('SVG cache: ${PictureProvider.cacheCount} items'),
+            Expanded(
-            const Spacer(),
+              child: Text('SVG cache: ${PictureProvider.cacheCount} items'),
+            ),
+            const SizedBox(width: 8),
             RaisedButton(
               onPressed: () {
                 PictureProvider.clearCache();
@@ -132,6 +137,18 @@ class DebugPageState extends State<DebugPage> {
             ),
           ],
         ),
+        Row(
+          children: [
+            const Expanded(
+              child: Text('Glide disk cache: ?'),
+            ),
+            const SizedBox(width: 8),
+            RaisedButton(
+              onPressed: () => ImageFileService.clearSizedThumbnailDiskCache(),
+              child: const Text('Clear'),
+            ),
+          ],
+        ),
         const Divider(),
         FutureBuilder(
           future: _dbFileSizeLoader,
@@ -140,8 +157,10 @@ class DebugPageState extends State<DebugPage> {
             if (snapshot.connectionState != ConnectionState.done) return const SizedBox.shrink();
             return Row(
               children: [
-                Text('DB file size: ${formatFilesize(snapshot.data)}'),
+                Expanded(
-                const Spacer(),
+                  child: Text('DB file size: ${formatFilesize(snapshot.data)}'),
+                ),
+                const SizedBox(width: 8),
                 RaisedButton(
                   onPressed: () => metadataDb.reset().then((_) => _startDbReport()),
                   child: const Text('Reset'),
@@ -157,8 +176,10 @@ class DebugPageState extends State<DebugPage> {
             if (snapshot.connectionState != ConnectionState.done) return const SizedBox.shrink();
             return Row(
               children: [
-                Text('DB date rows: ${snapshot.data.length}'),
+                Expanded(
-                const Spacer(),
+                  child: Text('DB date rows: ${snapshot.data.length}'),
+                ),
+                const SizedBox(width: 8),
                 RaisedButton(
                   onPressed: () => metadataDb.clearDates().then((_) => _startDbReport()),
                   child: const Text('Clear'),
@@ -174,8 +195,10 @@ class DebugPageState extends State<DebugPage> {
             if (snapshot.connectionState != ConnectionState.done) return const SizedBox.shrink();
             return Row(
               children: [
-                Text('DB metadata rows: ${snapshot.data.length}'),
+                Expanded(
-                const Spacer(),
+                  child: Text('DB metadata rows: ${snapshot.data.length}'),
+                ),
+                const SizedBox(width: 8),
                 RaisedButton(
                   onPressed: () => metadataDb.clearMetadataEntries().then((_) => _startDbReport()),
                   child: const Text('Clear'),
@@ -191,8 +214,10 @@ class DebugPageState extends State<DebugPage> {
             if (snapshot.connectionState != ConnectionState.done) return const SizedBox.shrink();
             return Row(
               children: [
-                Text('DB address rows: ${snapshot.data.length}'),
+                Expanded(
-                const Spacer(),
+                  child: Text('DB address rows: ${snapshot.data.length}'),
+                ),
+                const SizedBox(width: 8),
                 RaisedButton(
                   onPressed: () => metadataDb.clearAddresses().then((_) => _startDbReport()),
                   child: const Text('Clear'),
@@ -208,8 +233,10 @@ class DebugPageState extends State<DebugPage> {
             if (snapshot.connectionState != ConnectionState.done) return const SizedBox.shrink();
             return Row(
               children: [
-                Text('DB favourite rows: ${snapshot.data.length} (${favourites.count} in memory)'),
+                Expanded(
-                const Spacer(),
+                  child: Text('DB favourite rows: ${snapshot.data.length} (${favourites.count} in memory)'),
+                ),
+                const SizedBox(width: 8),
                 RaisedButton(
                   onPressed: () => favourites.clear().then((_) => _startDbReport()),
                   child: const Text('Clear'),
@@ -228,8 +255,10 @@ class DebugPageState extends State<DebugPage> {
       children: [
         Row(
           children: [
-            const Text('Settings'),
+            const Expanded(
-            const Spacer(),
+              child: Text('Settings'),
+            ),
+            const SizedBox(width: 8),
             RaisedButton(
               onPressed: () => settings.reset().then((_) => setState(() {})),
               child: const Text('Reset'),

lib/widgets/fullscreen/fullscreen_body.dart

@@ -5,7 +5,6 @@ import 'package:aves/model/collection_lens.dart';
 import 'package:aves/model/filters/filters.dart';
 import 'package:aves/model/image_entry.dart';
 import 'package:aves/utils/change_notifier.dart';
-import 'package:aves/utils/constants.dart';
 import 'package:aves/widgets/album/collection_page.dart';
 import 'package:aves/widgets/common/action_delegates/entry_action_delegate.dart';
 import 'package:aves/widgets/common/image_providers/thumbnail_provider.dart';
@@ -477,7 +476,8 @@ class _FullscreenVerticalPageViewState extends State<FullscreenVerticalPageView>
 
   void _onImageChanged() async {
     await UriImage(uri: entry.uri, mimeType: entry.mimeType).evict();
-    await ThumbnailProvider(entry: entry, extent: Constants.thumbnailCacheExtent).evict();
+    // TODO TLAD also evict `ThumbnailProvider` with specified extents
+    await ThumbnailProvider(entry: entry).evict();
     if (entry.path != null) await FileImage(File(entry.path)).evict();
     // rebuild to refresh the Image inside ImagePage
     setState(() {});

lib/widgets/fullscreen/image_view.dart

@@ -56,10 +56,7 @@ class ImageView extends StatelessWidget {
     // if the hero tag wraps the whole `PhotoView` and the `loadingBuilder` is not provided,
     // there's a black frame between the hero animation and the final image, even when it's cached.
 
-    final thumbnailProvider = ThumbnailProvider(
+    final fastThumbnailProvider = ThumbnailProvider(entry: entry);
-      entry: entry,
-      extent: Constants.thumbnailCacheExtent,
-    );
     // this loading builder shows a transition image until the final image is ready
     // if the image is already in the cache it will show the final image, otherwise the thumbnail
     // in any case, we should use `Center` + `AspectRatio` + `Fill` so that the transition image
@@ -86,7 +83,7 @@ class ImageView extends StatelessWidget {
             mimeType: entry.mimeType,
             colorFilter: Constants.svgColorFilter,
           ),
-          placeholderBuilder: (context) => loadingBuilder(context, thumbnailProvider),
+          placeholderBuilder: (context) => loadingBuilder(context, fastThumbnailProvider),
         ),
         backgroundDecoration: backgroundDecoration,
         scaleStateChangedCallback: onScaleChanged,
@@ -107,7 +104,7 @@ class ImageView extends StatelessWidget {
         // we still provide a `loadingBuilder` in that case to avoid a black frame after hero animation
         loadingBuilder: (context, event) => loadingBuilder(
           context,
-          imageCache.statusForKey(uriImage).keepAlive ? uriImage : thumbnailProvider,
+          imageCache.statusForKey(uriImage).keepAlive ? uriImage : fastThumbnailProvider,
         ),
         loadFailedChild: const EmptyContent(
           icon: AIcons.error,